The Alpen 6pc HSS Cobalt Stub Drill Set is designed for high-efficiency drilling with reinforced web for enhanced performance. These drills are particularly effective for working with stainless steel, acid-resisting steel, and spring steel. Sizes : 2.0mm, 3.0mm, 4.0mm, 5.0mm, 6.0mm, 8.0mm Brand : Alpen Special Features : 5% cobalt-alloyed for high efficiency and durability Reinforced web for enhanced strength Specially suitable for stainless steel, acid-resisting steel, and spring steel Break-resistant with a short, stable design Highly accurate centring for precision drilling Industrial quality for demanding applications